Project: A new ornithomimosaur from the Early Cretaceous Trinity Group of Arkansas

About the project

Whereas ornithomimosaurs (ostrich-mimic dinosaurs) are well known from Asia during in the Early Cretaceous, they are less well known from this time in North America. Represented by a single specimen consisting of pedal elements, a new North American taxon, Arkansaurus fridayi, gen. et sp. nov., consists of a nearly complete right foot, recovered from the Lower Cretaceous (Albian/Aptian) Trinity Group of Arkansas. Arkansaurus fridayi can be distinguished from other ornithomimosaurs based on differentiated pedal unguals, a laterally compressed third metatarsal that is ovoid in proximal view, and a distal ungual with a very weak flexor tubercle, lacking spurs. The condition of this third metatarsal suggest that Arkansaurus fridayi is more basal than other Asiatic ornithomimosaurs of similar age, but consistent with older North American forms. This specimen provides knowledge of a poorly understood radiation of ornithomimosaurs in Appalachia, and is the only known saurischian dinosaurian fossil from the state of Arkansas.

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ReBecca Hunt-Foster


1 published media groups owned by this project
1 published media groups associated with project specimens
1 project specimens
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UAM:74-16, Arkansaurus fridayi

Created 7/19/2017 at 13:28
Modified 7/20/2017 at 0:20